getdate_r

GETDATE(3)                 Linux Programmer's Manual                GETDATE(3)



NAME
       getdate() - convert a string to struct tm

SYNOPSIS
       #define _XOPEN_SOURCE
       #define _XOPEN_SOURCE_EXTENDED
       #include <time.h>

       struct tm *getdate (const char *string);

       extern int getdate_err;


       #define _GNU_SOURCE
       #include <time.h>

       int getdate_r (const char *string, struct tm *res);

DESCRIPTION
       The  function getdate() converts a string pointed to by string into the
       tm structure that it returns.  This tm structure may be found in static
       storage, so that it will be overwritten by the next call.

       In  contrast  to  strptime(3), (which has a format argument), getdate()
       uses the formats found in the file of which the full path name is given
       in  the  environment variable DATEMSK.  The first line in the file that
       matches the given input string is used for the conversion.

       The matching  is  done  case  insensitively.   Superfluous  whitespace,
       either in the pattern or in the string to be converted, is ignored.

       The  conversion  specifications  that  a  pattern can contain are those
       given for strptime(3).  One more conversion specification is accepted:

       %Z     Timezone name.

       When %Z is given, the value to be returned is initialised to  the  bro-
       ken-down time corresponding to the current time in the given time zone.
       Otherwise, it is initialised to the broken-down time  corresponding  to
       the current local time.

       When  only  the weekday is given, the day is taken to be the first such
       day on or after today.

       When only the month is given (and no year), the month is  taken  to  be
       the first such month equal to or after the current month.  If no day is
       given, it is the first day of the month.

       When no hour, minute and second are given, the current hour, minute and
       second are taken.

       If  no  date is given, but we know the hour, then that hour is taken to
       be the first such hour equal to or after the current hour.

RETURN VALUE
       When successful, this function returns a pointer to a struct tm.   Oth-
       erwise,  it  returns  NULL  and  sets  the global variable getdate_err.
       Changes to errno are unspecified.  The following values for getdate_err
       are defined:

       1   The DATEMSK environment variable is null or undefined.

       2   The template file cannot be opened for reading.

       3   Failed to get file status information.

       4   The template file is not a regular file.

       5   An error is encountered while reading the template file.

       6   Memory allocation failed (not enough memory available).

       7   There is no line in the file that matches the input.

       8   Invalid input specification.

NOTES
       Since  getdate() is not reentrant because of the use of getdate_err and
       the static buffer to return the result in, glibc provides a thread-safe
       variant.  The functionality is the same.  The result is returned in the
       buffer pointed to by res and in case of an error the  return  value  is
       nonzero with the same values as given above for getdate_err.

       The  POSIX 1003.1-2001 specification for strptime() contains conversion
       specifications using the %E or %O modifier, while  such  specifications
       are  not given for getdate().  The glibc implementation implements get-
       date() using strptime() so that automatically precisely the  same  con-
       versions are supported by both.

       The  glibc implementation does not support the %Z conversion specifica-
       tion.

ENVIRONMENT
       DATEMSK
              File containing format patterns.

       TZ, LC_TIME
              Variables used by strptime().

CONFORMING TO
       ISO 9899, POSIX 1003.1-2001

SEE ALSO
       localtime(3), strftime(3), strptime(3), time(3)



                                  2001-12-26                        GETDATE(3)